An electrical device like this requires a reverse leakage current of 10μA @ 1V.While the device is operating, the maximum voltage - Zener (Nom) is reduced to 4.7V.
ZM4732A-GS08 Features
reverse leakage current of 10μA @ 1V 10μA @ 1V is the maximum voltage (Tol)
ZM4732A-GS08 Applications
There are a lot of Vishay Semiconductor Diodes Division ZM4732A-GS08 applications of zener single diodes.